Amit Dekel

Abstract:

Real-life interactions rarely follow a fixed protocol dictating who acts when. This paper develops a conceptual framework for analyzing environments where multiple players (or coalitions) may have the right to act but no protocol of play sorts out who does. The central idea is simple: instead of imposing a fixed point condition on players' actions, we impose it on their intentions, capturing how they would act if they were to act. Intentions are interpreted through a behavioral model: a function that maps profiles of intentions into players' beliefs about how play will unfold. Our main result shows that a wide range of classical solution concepts (e.g. the Core, the vNM stable set, the Farsighted Stable Set) can be obtained within this framework by varying only the behavioral model. The behavioral models required to reproduce them, however, either ignore the free-play nature of the environment or rely on implausible restrictions on how players interpret others' intentions. By contrast, the most natural behavioral model - one where players account for the full profile of intentions -- yields a new solution concept that remains faithful to both rationality and free play.